import math

addStr = input("请输入加号:")
print(addStr)
subStr = input("请输入减号:")
print(subStr)
mulStr = input("请输入乘号:")
print(mulStr)
divStr = input("请输入除号:")
print(divStr)

def cal(x):
    perimeter = 2*math.pi*x
    area = math.pi*x*x
    return perimeter,area

inputNumber = input("请输入半径：")
tupleCal = cal(float(inputNumber))
print("周长是:%f ,面积是:%f" % (tupleCal[0],tupleCal[1]))